What is Fin Rot?

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What is Fin Rot?

This is a disease that commonly affects aquarium fish. Little is known about why fin rot occurs. Since aquariums are not a natural ecosystem, many environmental factors could come into play. Bacteria seem to play a pivotal role in causing disease. Despite the unknowns, this is easy to prevent and treat if you catch it well in advance.


At first symptoms of fin rot are very subtle and often go unnoticed. It's best to pay close attention to any changes to your fish's environment and appearance. Typical symptoms of fin rot are:

  • White fringe or discoloration on the fins
  • Cloudy appearance to fins
  • Fin fraying (a more advanced symptom)

Treatment and Prevention

The best treatment is prevention because once the disease sets in, it can be difficult to cure. The aquarium environment must be kept clean and pristine. We suggest these best practices for aquarium management:

  • Create a suitable ecosystem for the fish you are keeping. If possible, create a self-sustaining one.
  • Keep stress low. Avoid handling the fish often or rapidly moving the fish from one environment to the next.
  • Keep the fish's environment stable.
  • Make sure water quality is excellent and full of oxygen.
  • Add a food amount that the fish can eat entirely. Leftovers create a littered environment and breeding ground for nasty microbes.
  • Know which fish can live with each other beneficially. For example, betta fish do not mix well with other fish.
  • Use water filters, mechanical or natural such as water snails; they're good for keeping algae growth down too.

If your fish does develop fin rot symptoms, medical treatment of the water can help. Consult a fish vet or aquarium specialist who understands your fish well.   

As long as you keep the aquarium environment tidy and steady, your fish will live a long healthy life fin-rot-free. Let us help you create the ideal environment for your next aquarium pet and contact us.